1. Field
Embodiments of the present invention relate to a disk brake for vehicles in which friction pads are pressurized toward a disk through wedge members.
2. Description of the Related Art
In general, a disk brake is an apparatus which obtains braking force by pressurizing the outer surface of a disk, rotated together with a wheel, with friction pads. Among disk brakes, there is an Electro Wedge Brake (EWB) in which friction pads are pressurized toward a disk using wedge members in an inclined plane sliding manner. In such a EWB, for example, the wedge members are pushed along inclined planes by a driving device, and thus pressurize the friction pads toward the disk.
A EWB for vehicles includes a driving motor to operate wedge members, a screw shaft connected to a rotary shaft of the driving motor, the wedge members connected to the screw shaft so as to move forwards and backward in a direction parallel with the disk by means of operation of the driving motor, and a caliper housing provided with wedge parts formed in a shape corresponding to the wedge members to pressurize the wedge members toward the disk.
In the EWB, when the driving motor is operated to move the wedge members in one direction, the friction pads contact the disk, and simultaneously, the wedge members are pushed along inclined planes of the wedge parts to more firmly pressurize the friction pads toward the disk, thereby performing braking.
However, in case of such a conventional EWB for vehicles, if adhesion occurs due to moisture or other foreign substances between the disk and the wedge members under the condition that intervals between the disk and the wedge members are not sufficiently obtained due to vibration generated during driving of a vehicle, the friction pads may be attracted in the rotating direction of the disk according to rotation of the disk, and thereby unintended braking may be performed.